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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:46  
clear_day Transit: 12:51  
SunsetSet: 18:55 south
wb_twilight Astronomical TwilightWhat's Visible Now
All Constellations » Cygnus » 


Altitude: 4.8°   Azimuth: 321.4°   Direction: North-West

HR7551 is a variable hypergiant star in the constellation of Cygnus.

HR7551 visual magnitude is 6.44. Because of its reltive faintness, HR7551 should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.

The table below summarizes the key facts about HR7551:


HR7551 is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 4.8°
Azimuth: 321.4°
Direction: North-West

Celestial coordinates and finder chart of HR7551

HR7551 is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of HR7551 are provided in the following table:

19h 48m 50s
+33° 26’ 13”

The simplified sky map below shows the position of HR7551 in the sky:

Finder chart HR7551 star
Simplified finder chart for HR7551.

Visibility of HR7551 from your location

Location: Greenwich, United Kingdom edit_location_alt
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

Today's HR7551 rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 56.6°
Max altitude: 72.0°
Azimuth: 303.4°

Digitized Sky Survey image of HR7551

The image below is a photograph of HR7551 from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of HR7551 is 0.007 arcsec per year in Right Ascension and -0.002 arcsec per year in Declination and the associated displacement for the next 100000 years is represented with the red arrow.

Image of HR7551 star
DSS2 image of HR7551. The red arrow shows the motion of HR7551 during the next 100000 years (11.67 arcmin in Right Ascension and -3.33 arcmin in declination);

Distance of HR7551 from the Sun and relative movement

HR7551 is distant 2,217.69 light years from the Sun and it is moving towards the Sun at the speed of 10 kilometers per second.

680.27 pc
2,217.69 ly
-10 km/s
0.007 arcsec/year
-0.002 arcsec/year

Spectral properties of HR7551

HR7551 belongs to spectral class B0 and has a luminosity class of I corresponding to a hypergiant star.


The red dot in the diagram below shows where HR7551 is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of HR7551. Attribution: Richard Powell / CC BY-SA

Alternative designations of HR7551